1. Field of the Invention
This invention generally relates to bicycles and more particularly to an aid for increasing leg thrust that can be applied to the pedals by the bicycle rider while seated on the bicycle seat.
2. Description of the Related Art
Mountain bikes have been developed over the past ten years particularly for use off and on normal bike paths and roadways. These bicycles are particularly sturdy. They must be capable of being ridden over all types of terrain. In navigating such terrain, the rider often must stand on the pedals and position his or her weight ahead of or behind the saddle or seat. In this latter instance, the rider must be able to clear the seat easily. Thus narrow seats are preferred as opposed to the wide, cushioned seats often found on older model touring or recreational bicycles. The mountain bike rider also must go up much steeper slopes than most road bikes are designed for. Such slopes require very low gearing and substantial thrust applied to the pedals.
Thrust aids for use by a bicycle rider to enhance his or her leg thrust applied to the pedals have been proposed in several patents. U.S. Pat. No. 4,909,5306 discloses a short, contoured back support which is adapted to be attached to the contoured sides of the bicycle seat. This support projects above the rear of the seat several inches. U.S. Pat. No. 4,363,516 discloses an inverted U shaped thrust support which has its free legs fastened to the rails which support the bicycle seat on the seat post. This thrust support also projects upward behind the seat several inches.
Both of these supports are relatively permanently attached to the bicycle seat and because they project up above the seat, they preclude the rider positioning his or her weight well to the rear of the seat as may often be necessary on downhill runs on a mountain bike. Thus these supports, while effective to assist in applying maximum thrust to the pedals while sitting on the seat, are effectively unusable on mountain bikes. Other back rests and supports are disclosed in U.S. Pat. Nos. 4,475,770; 3,901,534; and 1,190,8312. None of these back rests are designed as an aid to the rider in applying force to the pedals. Accordingly, there is a need for a thrust support for a bicycle which can be readily utilized on mountain bikes. There is also a need for a thrust support which does not hinder the rider in negotiating downhill portions of a trail and still provide substantial support for leg thrusts while the rider is seated.